diff options
| -rw-r--r-- | arch/ia64/mm/init.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c index 65f9958db9f..1281c609ee9 100644 --- a/arch/ia64/mm/init.c +++ b/arch/ia64/mm/init.c @@ -382,13 +382,22 @@ ia64_mmu_init (void *my_cpu_data) if (impl_va_bits < 51 || impl_va_bits > 61) panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1); + /* + * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need, + * which must fit into "vmlpt_bits - pte_bits" slots. Second half of + * the test makes sure that our mapped space doesn't overlap the + * unimplemented hole in the middle of the region. + */ + if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) || + (mapped_space_bits > impl_va_bits - 1)) + panic("Cannot build a big enough virtual-linear page table" + " to cover mapped address space.\n" + " Try using a smaller page size.\n"); + /* place the VMLPT at the end of each page-table mapped region: */ pta = POW2(61) - POW2(vmlpt_bits); - if (POW2(mapped_space_bits) >= pta) - panic("mm/init: overlap between virtually mapped linear page table and " - "mapped kernel space!"); /* * Set the (virtually mapped linear) page table address. Bit * 8 selects between the short and long format, bits 2-7 the |